1. Field of the Invention
The present invention relates to a vehicle, and, more specifically, to a vehicle that is equipped with an external power supply part that is used to supply electric power to the outside of the vehicle, a controller for the vehicle, and a control method for the vehicle.
2. Description of Related Art
In recent years, plug-in hybrid vehicles that can be charged from a commercial power source are commercially available. Plug-in hybrid vehicles can also provide electric power to an electric device, power grid or the like outside the vehicle (which may be hereinafter also referred to as “external power supply”) (refer to Japanese Patent Application Publication No. 2007-236023 (JP 2007-236023 A), for example).
When the engine is frequently started, fuel consumption increases. It is, therefore, desirable for hybrid vehicles to avoid starting the engine as much as possible to reduce fuel consumption. Thus, techniques that are used to determine whether to start the engine of a hybrid vehicle have been proposed. For example, a controller for a hybrid vehicle that is disclosed in WO2011/125184 has a determination part that determines whether to start the internal combustion engine based on an allowable discharge capacity. The allowable discharge capacity indicates the electric power that the electric storage device can discharge.
A catalyst that is used to purify the exhaust gas is provided in an exhaust pipe that is coupled to the engine. The catalyst fulfills its purifying function when it is sufficiently warmed. Thus, for example, when the engine is started, warm-up to increase the temperature of the catalyst (which may be hereinafter also referred to as “catalyst warm-up”) is executed. For example, a controller for a hybrid vehicle that is disclosed in Japanese Patent Application Publication No. 2000-234539 (JP 2000-234539 A) maintains the engine speed at a predetermined level or higher to activate the catalyst as exhaust gas purifying means when the vehicle is in a power generation mode for external power supply.